This invention refers to a microgyroscope for determining rotational movements about an x and/or y and z axis, especially as a 3-D sensor, with a substrate, with several oscillating masses, with springs for fastening the oscillating masses to the substrate, and with drive elements for the oscillatory swinging of at least individual masses on the x, y axis in order to generate Coriolis forces by rotating the substrate, and with sensor elements for registering deflections of the masses owing to the generated Coriolis forces.
Micro-electro-mechanical (MEMS) gyroscopes are generally used for determining a rotational movement about an axis in an x-y-z system of coordinates. So rotational movements of the system about every one of the three axes can be determined, three such microgyroscopes are therefore needed. This is expensive and difficult to control, and the data are difficult to process too.
In order to create a three-dimensional gyroscope able to determine rotations in all three axes, D. Wood et al. suggested in the 1996 article “A monolithic silicone gyroscope capable of sensing about three axes simultaneously” the creation of a circular gyroscope with oscillatory masses arranged around a central anchor capable of determining tilting and rotational movements due to the occurring Coriolis forces. The disadvantage in this is the fact that the manufacture of such a sensor is difficult if not impossible, and the same can be said of how the moved masses should be driven. The designs of D. Wood et al. therefore remained merely theoretical.
In his article “Design and dynamics of an innovative microgyroscope against coupling effects, Nan-Chyuan Tsai also suggests a 3-D gyroscope. The disadvantage here is that an inner plate and an outer ring as well as four moved masses are available. The necessary spring constructions with low rigidity in two orthogonal rotational directions are prone to tolerance and difficult to build.
The task of this invention is therefore to build a very accurate, relatively economical 3-D micro gyro sensor that avoids the shortcomings mentioned above.